Welding of shackles

  • Safety Flash
  • Published on 15 December 2010
  • Generated on 12 July 2025
  • IMCA SF 08/10
  • 1 minute read

A Member has reported that in spite of clear work instructions and procedures to the contrary, shackles and hooks at the worksite were being regularly modified by welding.

What happened?

Rigging suppliers or individual worksites were carrying out welding modifications (mainly to shackles) after delivery from the manufacturer. This practice invalidates the manufacturer’s certificate and is potentially hazardous.

The welding of shackles (after delivery from manufacturer) has the effect of adversely altering the material properties and increases the risk of failure by various brittle modes. In addition to this increased risk, the nature of the failure is unpredictable, is not time dependant and cannot be prevented by inspection.

Our member recommends that all shackles and hooks that have been modified by welding should be removed from service. Equipment suppliers should be instructed not to modify or issue modified shackles or hooks for use on any worksite.

Example of shackle with welded modification performed by supplier

Example of shackle with welded modification performed by supplier

Example of shackle with welded modification performed at worksite

Example of shackle with welded modification performed at worksite

Latest Safety Flashes:

LTI: Hand injury during capstan maintenance

A crew member was injured when their hand was trapped between a wire clamp on the underside of the capstan and the deck.

Read more
High potential incident: Worker injured when opening a flanged assembly

A member of a team of workers dismantling subsea emergency shutdown valves (ESDV) on deck, was badly injured when hit by parts of a valve which were ejected with force.

Read more
Near miss: worker suffers electric shock

A member of a vessel crew suffered a mains electric shock when working on a crane pedestal.

Read more
Unsafe use of electrical equipment in cabins

Crew members were observed inserting 2-pin electrical chargers directly into 3-pin vessel sockets to power their personal equipment.

Read more
UK HSE: load falls from lorry and kills cyclist

A metal heat exchanger, weighing over 2.5 tons, fell from a lorry and killed a passing cyclist.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.